Imaging Sci Dent.  2016 Sep;46(3):223-227. 10.5624/isd.2016.46.3.223.

Developmental salivary gland depression in the ascending mandibular ramus: A cone-beam computed tomography study

• Chen CA
• Ahn Y
• Odell S
• Mupparapu
• Graham DM

• KMID: 2408255
• DOI: http://doi.org/10.5624/isd.2016.46.3.223

Abstract

A static, unilateral, and focal bone depression located lingually within the ascending ramus, identical to the Stafne's bone cavity of the angle of the mandible, is being reported. During development of the mandible, submandibular gland inclusion may lead to the formation of a lingual concavity, which could contain fatty tissue, blood vessels, or soft tissue. However, similar occurrences in the ascending ramus at the level of the parotid gland are extremely rare. Similar cases were previously reported in dry, excavated mandibles, and 3 cases were reported in living patients. A 52-year-old African American male patient was seen for pain in the mandibular teeth. Panoramic radiography showed an unusual concavity within the left ascending ramus. Cone-beam computed tomography confirmed this incidental finding. The patient was cleared for the extraction of non-restorable teeth and scheduled for annual follow-up.

Keyword

Cone-Beam Computed Tomography; Mandible; Parotid Gland; Salivary Glands

MeSH Terms

Adipose Tissue
Blood Vessels
Cone-Beam Computed Tomography*
Depression*
Humans
Incidental Findings
Male
Mandible
Middle Aged
Parotid Gland
Radiography, Panoramic
Salivary Glands*
Submandibular Gland

Figure

• 

  Fig. 1 A panoramic radiograph shows the well-corticated depression on the left ascending ramus.

• 

  Fig. 2 A cone-beam computed tomography panoramic reconstruction and coronal multi-planar reconstructed slice show the well-corticated depression in the ramus. Note the lingual location of the concavity.

• 

  Fig. 3 A cone-beam computed tomography 3-dimensional reconstruction of the mandible and maxilla shows the lingual depression through the thinned or perforated buccal aspect of the left mandibular ramus (top). A sagittal reconstructed slice of the left side shows the details of the concavity (bottom).

• 

  Fig. 4 An axial cone-beam computed tomography reconstruction showing thinning of the buccal cortex and the lingual location of the depression on the left ramus (arrow).

• 

  Fig. 5 An axial cone-beam computed tomography slice of a 3-dimensional reconstruction with soft tissue overlay and coloration shows the posterior and lingual location of the concavity within the left ramus. The short arrow points to the lingual concavity and the long arrow points to the left styloid process. Note that the stylomandibular tunnel is the space between the styloid process and the ramus of the mandible, which is immediately adjacent to the parotid gland.

• 

  Fig. 6 A diagrammatic representation of Meckel's cartilage (mandible) during embryonic development shows the relationship and proximity of the developing parotid gland.

Reference

1. Stafne EC. Bone cavities situated near the angle of the mandible. J Am Dent Assoc. 1942; 29:1969–1972.

2. Kim JS. Multilocular developmental salivary gland defect. Imaging Sci Dent. 2012; 42:261–263.

3. Barker GR. A radiolucency of the ascending ramus of the mandible associated with invested parotid salivary gland material and analogous with a Stafne bone cavity. Br J Oral Maxillofac Surg. 1988; 26:81–84.

4. Minowa K, Inoue N, Sawamura T, Matsuda A, Totsuka Y, Nakamura M. Evaluation of static bone cavities with CT and MRI. Dentomaxillofac Radiol. 2003; 32:2–7.

5. Guizetti B, Radlanski RJ. Development of the parotid gland and its closer neighboring structures in human embryos and fetuses of 19-67 mm CRL. Ann Anat. 1996; 178:503–508.

6. Carlson GW. The salivary glands. Embryology, anatomy and surgical applications. Surg Clin North Am. 2000; 80:261–273.

7. Campos PS, Panella J, Crusoe-Rebello IM, Azevedo RA, Pena N, Cunha T. Mandibular ramus-related Stafne's bone cavity. Dentomaxillofac Radiol. 2004; 33:63–66.

8. Wolf J. Bone defects in mandibular ramus resembling developmental bone cavity (Stafne). Proc Finn Dent Soc. 1985; 81:215–221.

9. Shields ED. Technical note: Stafne static mandibular bone defect-further expression on the buccal aspect of the ramus. Am J Phys Anthropol. 2000; 111:425–427.

10. Mann RW, Shields ED. Cavitation defects on the lingual ramus: a further expression of Stafne's defect. J Craniofac Genet Dev Biol. 1992; 12:167–173.

11. Lee KH, Thiruchelvam JK, McDermott P. An unusual presentation of Stafne bone cyst. J Maxillofac Oral Surg. 2015; 14:841–844.

12. Philipsen HP, Takata T, Reichart PA, Sato S, Suei Y. Lingual and buccal mandibular bone depressions: a review based on 583 cases from a world-wide literature survey, including 69 new cases from Japan. Dentomaxillofac Radiol. 2002; 31:281–290.